Sudden infant death syndrome (SIDS) is unexpected death of a child less than one year old. Diagnosis requires that the death remains unexplained even after investigation. Cause of SIDS is unknown so far. Several possible factors including asphyxia during sleep have been proposed based on clinical research and observation of medical community. In addition to infants, those with cardiopulmonary dysfunction, elders, those with limited mobility, those with obstructive sleep apnea, etc., may suffer from asphyxia during sleep due to pauses in breathing or due to blockage of airways from presence of secretions or foreign materials.
In order to prevent asphyxia during sleep, breath monitoring systems have been widely used in clinical research or in home medical care. However, a conventional breath monitoring system only provides a warning output to inform a caregiver when breath of a person under monitoring is determined to be abnormal, such that the caregiver can come to deal with the person. Before the caregiver arrives, the conventional breath monitoring system is unable to actively perform preliminary emergency procedures on the person.